/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.cassandra.cql3.ast;

/**
 * Marker interface of what is allowed in a reference
 */
public interface ReferenceExpression extends Expression
{
    @Override
    default ReferenceExpression visit(Visitor v)
    {
        return v.visit(this);
    }

    default Symbol asSymbol()
    {
        if (!(this instanceof Symbol))
            throw new IllegalStateException("Unable to convert type " + getClass() + " to Symbol");
        return (Symbol) this;
    }

    Symbol column();
}
